Builtin functions in at least most previous versions of Mathematica have required capitalized names; I think it's got to do with disambiguation vs user-defined

Builtin functions in at least most previous versions of Mathematica have required capitalized names; I think it's got to do with disambiguation vs user-defined functions (e.g. builtin `Sin` is the mathematical sine funciton, while the user-defined `sin` prints the seven deadly sins for whatever reason -- you still retain access to both this way). As for square brackets for parameters, it's unconventional, for sure, but not ambiguous because list literals use curly braces anyway.